Perform Group provides sports data for betting companies such as William Hill. Photograph: Mike Egerton

Digital sports rights company Perform Group saw its share price more than halve on Thursday – stripping more than £600m off its stock market value – after issuing a profits warning as trading deteriorated in the final three months of the year.

The company, which provides sports videos and data to consumers and betting companies such as Bet 365 and William Hill, downgraded its profit forecast this year after revealing a significant deterioration in advertising and sponsorship revenues in the fourth quarter.

He said the company "bit off more than it could chew in 2013" with a "complex and massively time consuming" series of contract re-negotiations with bookmakers for its Watch & Bet service, on top of acquisitions, fundraising and trying to prepare for the World Cup next year.

"In such a high growth model perhaps … the real mistake here is not being brutally prudent and conservative among a plethora of unknowns," said Reynolds.

Jefferies has downgraded its full-year 2012 profit forecast by 27%, from £52m to £38m, and down 32% next year from £74m to £50m.

The company said that the fourth quarter is critical to its business, accounting for a third of annual revenues and 50% of profits, "consequently the revenue shortfall will directly impact adjusted [profits]".

Perform said its operations in the US and Germany were particularly badly hit.

"We are disappointed with the performance of the business in the fourth quarter against our expectations and as a consequence this has an impact on our outlook for 2014," said Oliver Slipper, joint chief executive of Perform. "Whilst the issues we have experienced in the second half of 2013 are unsatisfactory, as a management team we are fully committed to continuing to grow Perform."

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